Glanders and strangles are two bacterial diseases that affect equines, yet they differ in origin, risk, and management. Understanding these differences helps owners, veterinarians, and stable managers protect herd health without unnecessary alarm.
Both illnesses can trigger fever, nasal discharge, and lymph node changes, so telling them apart at the barn door can be tricky. A quick visual check is never enough; knowing what each disease does inside the body guides smarter next steps.
What Glanders Really Is
Glanders is caused by Burkholderia mallei, a bacterium that survives only in host tissue and moist environments. It spreads through direct contact with infected horses, shared tack, or contaminated feed buckets.
Historically linked to working equines in humid regions, the disease now surfaces sporadically where biosecurity lapses occur. Chronic carriers can shed the organism for months before anyone notices a problem.
The germ enters through mouth, nose, or skin cuts, then heads for the lungs, skin, and internal organs. Unlike many infections, it can form nodules that later ulcerate, making early detection harder.
Forms of Glanders in Horses
Three common forms exist: pulmonary, nasal, and cutaneous. Each targets a different body site yet stems from the same bacterium.
Pulmonary cases show coughing and deeper breathing effort, often misread as mild flu. Nasal forms bring thick, sticky nasal discharge and painful ulcers inside the nostrils.
Cutaneous glands presents as firm nodules along the legs or belly that rupture and leave star-shaped scars. Any one form can appear alone or blend with another, complicating field diagnosis.
What Strangles Is
Strangles is caused by Streptococcus equi subspecies equi, a highly contagious bacterium that sticks to equine tonsils. It spreads via nasal droplets, shared water troughs, and hands or tools that touch infected pus.
The name comes from the swollen lymph nodes that sometimes press on the windpipe, giving a “strangled” breathing sound. Most cases occur in young horses housed closely together.
After a short incubation, fever spikes and thick yellow discharge appears from both nostrils. Within days, the lymph nodes under the jaw swell, forming abscesses that eventually burst outward.
Progression of Strangles
Early signs include depression, reduced appetite, and a temperature above normal. Owners often first notice a wet, sticky muzzle and a horse that hangs back from feed.
As abscesses mature, the jawline becomes hot and painful to touch. Some animals develop a soft cough when the swelling presses on the throat.
In uncomplicated cases, the abscesses open, drain creamy pus, and the horse recovers within weeks. Complications arise when abscesses form deeper in the body or when guttural pouches retain dried pus.
Key Biological Differences
Burkholderia mallei is a stealth pathogen that hides inside cells, while Streptococcus equi sits on mucosal surfaces and triggers rapid pus formation. This cellular hiding makes glanders harder to clear and more prone to chronic infection.
Strangles rarely kills healthy adults, but glanders can progress to internal organ nodules that prove fatal. The immune response also differs: strangles sparks a strong but local reaction, whereas glanders can slip past early defenses.
Another contrast lies in survivability outside the host. Strangles bacteria die quickly in dry air, while glanders organisms persist slightly longer in damp straw or leather, demanding stricter disinfection.
Transmission Routes Compared
Strangles spreads nose-to-nose through droplets, shared bits, or human hands. Glanders adds another layer: skin contact with ulcerated lesions or contaminated equipment can seed new cases.
Flies may mechanically carry both agents, yet glanders poses a higher theoretical risk because ulcers ooze viable bacteria. Any open wound on a handler’s hand could serve as an entry point for glanders, a scenario almost unheard of with strangles.
Consequently, separate grooming kits and single-use thermometers matter more when glanders is suspected. For strangles, the bigger worry is aerosol spread during early fever days.
Clinical Signs That Set Them Apart
Strangles classically shows hot, swollen lymph nodes under the jaw that ripen into visible abscesses. Glanders lymph nodes may enlarge, yet they rarely abscess externally; instead, nasal ulcers and star-shaped skin nodules dominate.
Horses with strangles often remain bright between fever spikes, eating hay if chewing hurts less. Glanders cases tend to decline faster, with weight loss and deeper lethargy as internal organs become involved.
A simple rule of thumb: external abscesses point toward strangles; internal nodules and ulcers hint at glanders. Neither sign is absolute, so veterinary testing is essential.
Discharge Characteristics
Strangles discharge starts watery, then thickens to creamy yellow pus dripping from both nostrils. The odor is mild, similar to sour milk.
Glanders discharge is stickier, sometimes blood-tinged, and carries a sweeter, sickly smell. It may crust inside the nostril and leave raw, punched-out ulcers when removed.
Owners can gently wipe the muzzle with a clean paper towel, seal it in a bag, and present it to the vet for culture. Never reuse the towel on another horse.
Diagnostic Approach
Veterinarians begin with a physical exam, then collect swabs from the nasal cavity or draining abscess. For strangles, a simple strep culture or PCR confirms the bug within days.
Glanders demands stricter biosafety: blood tests, nasal swabs, and sometimes biopsy of skin nodules are collected while wearing gloves and mask. Some countries require state labs to run the tests due to regulatory concerns.
Both diseases can produce false negatives if sampling is done too early or after antibiotics. Re-testing two weeks later is common when suspicion remains high.
On-Farm Sample Handling
Use double-tipped swabs: one for each nostril, snapped into separate transport tubes. Label with horse name, date, and clinical sign observed.
Keep tubes cool but not frozen, and deliver to the lab within 24 hours. Avoid leaving swabs in hot tack rooms where bacterial DNA degrades.
If overnight shipping is needed, pack tubes with ice packs in a padded envelope, then notify the lab so staff can expect the package.
Treatment Philosophies
Strangles therapy balances supportive care with careful abscess management. Hot-packing swollen nodes encourages natural drainage, while non-steroidal drugs ease fever.
Antibiotics are reserved for horses with breathing distress or complications, because early use can delay abscess maturation. Once nodes burst, flushing with dilute antiseptic keeps the area clean.
Glanders treatment is more aggressive due to its zoonotic risk and chronic nature. Long courses of specific antibiotics, chosen after sensitivity testing, are mandatory.
Euthanasia is often elected for confirmed glanders cases because carriers can shed silently and threaten public health. Strangles rarely ends this way unless complications spiral.
Supportive Nursing at the Barn
Isolate the sick horse in a well-ventilated stall with dust-free bedding. Offer soaked hay cubes to reduce chewing pain when lymph nodes are tense.
Provide a raised water bucket so the horse need not lower its head against painful swellings. Clean and refill twice daily to encourage drinking and flush toxins.
For glanders cases under treatment, handlers must wear disposable gloves and coveralls, laundering separately in hot water with added disinfectant.
Biosecurity Protocols for Each Disease
Strangles calls for a “traffic light” system: red zone for infected animals, amber for exposed, green for clean. Footbaths, separate tools, and hand washing stations reduce crossover.
Glanders demands stricter lockdown: total farm quarantine, state notification, and often depopulation of confirmed cases. Tack, trailers, and even walls receive chlorine-based disinfectant.
Record all movements for at least six months. Digital logs help trace back if a new case pops up after the farm appears clear.
Cleaning Equipment the Right Way
Remove organic matter first; dried pus shields bacteria from disinfectants. Scrub bits with warm soapy water, then soak in chlorhexidine solution for 10 minutes.
Leather bridles need special care: wash with glycerin soap, rinse, and wipe with 70% alcohol. Allow to dry in sunlight, because UV light adds extra kill power.
Shared thermometers and stethoscopes should be wiped with alcohol swabs between horses. Keep a labeled zip bag for “dirty” items awaiting cleaning.
Vaccination Landscape
Commercial strangles vaccines exist in intranasal and intramuscular forms. They do not prevent every infection, but they soften clinical signs and reduce abscess size.
Vaccination timing matters: avoid giving during an outbreak, because stressed immune systems can react poorly. Consult a vet to schedule boosters before high-risk seasons like autumn shows.
No licensed glanders vaccine is available worldwide. Prevention therefore relies on strict import testing, quarantine, and rapid culling of positives.
Deciding Whether to Vaccinate Against Strangles
Horses that travel to fairs, breeding farms, or communal trails face higher exposure. If your horse never leaves the property and newcomers are quarantined, risk drops sharply.
Discuss with your vet the farm’s previous outbreak history and local disease pressure. Sometimes the cost and mild vaccine reaction outweigh the benefit in closed herds.
Keep a written record of vaccine dates and batch numbers; this speeds investigations if breakthrough cases occur.
Long-Term Management After Outbreak
Post-strangles, screen the entire herd with guttural pouch endoscopy to find silent carriers. These horses shed strep in small pockets of dried pus and ignite new waves months later.
Retest any horse with a history of nasal discharge twice, three weeks apart. Two negative PCR results clear the animal for normal turnout.
After glanders, regulatory officials typically require a minimum 90-day closure and multiple rounds of whole-herd testing. Only when every animal tests negative twice can the farm regain disease-free status.
Rebuilding Herd Confidence
Resume group turnout gradually, starting with small pods of tested negatives. Observe for cough or nasal drip daily for another month.
Invite your vet back for a final sweep of guttural pouches or nasal swabs before big events. Document each test for future buyers who ask about herd health history.
Share transparent updates with boarders; open communication prevents rumors and keeps clients loyal.
Human Health Considerations
Glanders is classified as a potential zoonotic agent, meaning humans can contract it through skin cuts or inhalation. Lab workers and veterinarians face the highest risk during post-mortem exams.
Symptoms in people range from fever and muscle aches to skin ulcers and pneumonia. Prompt medical care and antibiotics are essential.
Strangles almost never jumps to humans, so routine barn work carries negligible risk. Still, basic hygiene like hand washing after handling discharge remains wise.
Protecting Yourself at the Barn
Wear nitrile gloves when treating nasal discharge or abscesses. Dispose of gloves in sealed trash to avoid accidental reuse.
Cover open cuts with waterproof bandages before entering isolation stalls. Change clothes and shower before heading home to vulnerable family members.
If you develop flu-like signs after working with a glanders suspect, tell your physician about the exposure history immediately. Early treatment prevents severe complications.
Take-Home Checklist for Owners
Isolate any horse with fever plus nasal discharge within hours, not days. Call the vet before second-guessing.
Label all gear and enforce separate buckets. A strip of colored tape costs pennies and saves weeks of outbreak control.
Keep a simple log: temperature, appetite, discharge color, and lymph node size. Patterns guide faster, cheaper diagnostics.
Finally, remember that calm, consistent biosecurity beats panic every time. Your horse depends on clear thinking and swift, simple actions.